MSV-2035 Astronomy Document - Inside Design - FINAL - FINAL

Astronomy & Astrophysics 26 all galaxies are surrounded by the so-called circumgalactic medium. While these observations have enabled astronomers to build a framework of galaxy formation and evolution, important breakthrough in our understanding will be possible only when detailed spectroscopic studies of the distant faint galaxies are possible. This is at present beyond the capabilities of the existing telescopes. Thanks to these large telescopes it is now possible tomeasure the rate at which distant galaxies form stars, the total mass contained in the stars and the rate at which gas is ejected from the distant galaxies in the form of winds. However, due to Earth's atmosphere most of the distant galaxies are not spatially resolved by the ground based observations. Measuring the spatial distribution of above mentioned quantities is very important for building a complete understanding of various physical processes associated with star formation in distant galaxies. Larger facilities with adaptive optics capabilities and integral field spectroscopic techniques will enable achieving the same. Accurate tracking of the motion of stars in the central regions of MilkyWay has led to the measurement of the mass of the central black hole. Kinematics of stars is one of the cleaner ways tomeasure the black hole mass at the center of galaxies.At present this technique is applicable only to our Galaxy. Extending this to nearby galaxies is important and possible only using larger telescopes (i.e 30-meter class telescopes) with higher spatial resolution imaging capabilities. Observations of distant supernovae have led to the accurate measurement of the Hubble constant and the confirmation of the accelerated expansion of the Universe. Spectroscopic observations of various transients have revealed their chemical composition and related nuclear processes and the nature of the ambient mediumas well as that of the intervening objects between us and the transients. Similarly, the 10- meter class telescopes have played a major role in detailed studies of the temporal evolution of the first electromagnetic counterpart of a neutron star-neutron star merger that produced detectable Gravitational Waves. They also played a crucial role in understanding the host galaxies of GRBs and FRBs. Spectroscopic studies of transients occurring at large red shifts are important to understand the chemical composition and star formation during the early Universe, and this will only be possible with the future, larger telescopes. Precise measurements of radial velocity and transit properties have enabled the detection of over five thousand planets around stars outside of our solar system. It is now possible to characterise the atmospheric properties of some of those exoplanets. High contrast and high spatial resolution imaging and spectroscopic capabilities are proposed by the international community for pushing this research to the next level. It has now been recognized by the international community that to make further progress in the next decade, it is important to build larger aperture telescopes (typically of 20–50-meter diameter). The main aim is to have large collecting area and achieve sharpest possible images (beating the atmospheric blurring) over a wide wavelength range. However, such extremely large telescopes can only be built using large international collaboration. As of now there are three such telescopes being built by the international community: (1) Thirty Meter Telescope (TMT), (2) Giant Magellan Telescope (GMT) and (3) European Large Telescope (ELT). These telescopes will start operation sometime in the next decade and are expected to serve the international community for several decades to come. • • • • MEGA SCIENCE VISION-2035